Why have nightsurfer if it doesnt exist?

Myself and my wife have had telkom basic internet with a 10GB cap now for a few months, Iv never had anything to complain about. The service has been surprisingly good and we are quite happy but the once in a blue moon I try to download something during nightsurfer hours, it only eats into my normal daily cap, as the nightsurfer doesnt exist. I was up quite late on saturday night for a change and decided to download something, the next morning we got a message that our normal cap is used up. It was only 3.80gb.<br> <br> false advertising at its best!!